The feeding value of ammoniated flax straw,wheat straw and wheat chaff for beef cattle

Two experiments were conducted to assess the feeding value of ammoniated and untreated flax straw, wheat straw and wheat chaff in comparison to a mixed bromegrass/alfalfa hay. Anhydrous ammonia was applied to the crop residues at the rate of 35 kg t⁻¹ dry matter. In the first experiment, the effect of ammoniation on crude protein, acid detergent fibre (ADF), neutral detergent fibre (NDF) and acid detergent lignin (ADL), digestible organic matter in vitro and in vivo (DOM%), ADF and NDF digestibility of the crop residues was determined. In the second experiment, ammoniated flax straw, ammoniated wheat straw, ammoniated and untreated wheat chaff, each supplemented with barley, were compared to bromegrass/alfalfa hay as feed sources for wintering beef cows.Ammoniation increased the crude protein content of the crop residues ∼2-fold. Wheat straw DOM in vitro and in vivo was not increased by ammoniation. Ammoniation increased the DOM in vitro of wheat chaff from 36.3 to 46% and flax straw from 35.2 to 46.3%. The DOM in vivo increased from 53.3 to 63.4% (P < 0.05) for wheat chaff and from 33.9 to 58.4% (P < 0.05) for flax straw following ammoniation. Digestibility of ADF increased from 9.9 to 43.9% (P < 0.05) and of NDF from −0.6 to 37.9% (P < 0.05) in flax straw with ammoniation. Non-significant increases in ADF and NDF digestibility were observed for all other crop residues. Lignin content was not changed in the crop residues by ammoniation.In the winter feeding trial, young cows gained more weight than older cows (P < 0.05). Average daily gains of cows were greatest for hay followed by ammoniated flax straw, ammoniated chaff, untreated chaff and ammoniated wheat straw rations (P < 0.05). Increases in backfat in the younger cows was greatest with hay and ammoniated flax straw, followed by ammoniated chaff and ammoniated wheat straw (P < 0.05). Untreated chaff caused no increase in backfat thickness.Ammoniated flax straw (3.2 kg day⁻¹) given with barley (5.6 kg day⁻¹), is similar in feeding value to medium quality bromegrass/alfalfa hay. Furthermore, wheat chaff and ammoniated wheat chaff show good potential as alternatives to hay in winter feeding.     

Studies on blood biochemical constituents and rumen fermentation in growing buffalo calves fed ammoniated straw-based rations supplemented with different protein sources

Studies were done on blood biochemical constituents and rumen fermentation pattern of growing buffalo calves fed ammoniated wheat straw (UAS)-based rations supplemented with three different protein supplements. Eighteen buffalo calves (140 kg) were divided into three groups of six calves each and were fed on UAS supplemented with a concentrate mixture (roughage:concentrate ratio 58:42) containing 8% (or 3.5% of total ration) untreated groundnut cake (GNC) (group I), 8% formaldehyde treated GNC (group II) and 8% fish meal (group III), respectively, for 19 weeks. During this growth study, blood biochemistry was studied. Rumen fermentation study was done on three fistulated growing buffalo calves using a 3×3 Latin square switch over design. Blood glucose and ammonia-N did not differ significantly among the treatments. However, blood urea-N of calves in group III was higher (P<0.05) than in groups I and II, but the latter two did not differ from each other in this respect. Total protein in group I was comparable to group II and group III which were significantly different from each other. The rumen pH, total volatile fatty acids, ammonia-N and total protozoal count were similar, however, total N and TCA insoluble N in group II and group III were higher (P<0.01) than in group I. Fish meal containing diet favoured holotrichs, whereas, protected GNC containing diet favoured spirotrichs as indicated by significantly higher count. It was concluded that the beneficial effects of supplementing formaldehyde protected GNC at 8% in the concentrate mixture to the UAS-based diets were greater than supplementation of unprotected GNC or low quality fish meal in ration of buffalo calves growing at 400 g because of improved rumen fermentation, absorption and metabolism of nutrients as observed in blood biochemistry.     

The effect of ammoniation on the intake and nutritive value of straw

Studies were conducted to compare the increases in dry matter digestibility (DMD) in vitro and in vivo and to determine the metabolisable energy (ME) value of straw ammoniated at ambient temperature. Two stacks of straw sealed with polyethylene were allowed to react with 3% (w/w) anhydrous NH₃ for 30 and 56 days, respectively. Both DMD in vitro and nitrogen tests were carried out over an eight-week period subsequent to opening the stacks. Digestibility in vivo was measured with 12 wether lambs. The non-treated and ammoniated straws were given ad libitum, with a supplement of either ground barley or a lamb concentrate which contained 16% crude protein (CP).There was a mean increase of 15 percentage units in DMD in vitro for the ammoniated straw irrespective of whether it was treated for 30 or 56 days. The corresponding increase in mean DMD in vivo was 14.2 units. The CP content of the straw was increased from 3.1 to 7.6%. The increase in DMD in vitro and total N content was maintained throughout the sampling period. Approximately 58% of the anhydrous NH₃ added to the straw appeared to have been irreversibly “bound” to the straw. The ME values for the ammoniated straw were 6.78 and 7.49 MJ/kg when the straw was supplemented with either barley or the lamb concentrate, respectively. Straw ammoniation had a marked effect on intake. The overall increase in intake was 70% for the treated compared with the non-treated material.     

Digestion of organic matter and nitrogen in ammoniated barley straw

Barley straw, either treated with anhydrous ammonia (40 g/kg for 28 days) or untreated, was chaffed and given to sheep in an intake and digestibility trial, or was ground and incubated in nylon bags in the rumen of sheep fed on lucerne or untreated or ammoniated straw.Ammoniation increased the N content from 2.45 to 10.63 g/kg dry matter (DM). Of the increment, 67% was retained in water-soluble form and 11.5% was in the cell wall organic matter (CWOM). The water-soluble N appeared to be retained by sheep as well as urea-N given with untreated straw; digestibility coefficients obtained in vivo, and by nylon bag incubation, suggested that N in CWOM was largely unavailable.Ammonia treatment increased the potential digestibility (measured by nylon bag incubation) of DM and CWOM by 23 and 29%, respectively. Digestibility in vivo of OM increased from 0.42 to 0.60 and of CWOM from 0.48 to 0.67. Intake of ammoniated straw increased over the 23-day feeding period, while that of untreated straw given with or without urea was constant or declined.     

Effects of carvacrol on defects of ischemia-reperfusion in the rat liver

Many plants found in nature have been used to treat various illnesses. One such plant is oregano (Kekik in Turkish). Health beneficial effects of carvacrol obtained from oregano oil have been shown scientifically. We have investigated the comparative effects of carvacrol in the liver of rats subjected to ischemia-reperfusion defect, with silymarin. To test the effects we formed four groups using male Wistar albino rats. Group I was control. The other three groups of animals were administered 60 min prior to surgical operation single doses of physiological serum, carvacrol and silymarin, respectively. Group II, III and IV animal were subjected to 45 min long liver ischemia and 60 min reperfusion. Blood and tissue samples were collected for biochemical and histological analysis following the test.AST and ALT values obtained after biochemical analysis of the serums showed statistically significant difference in group II than the other three groups. A statistical evaluation of the serum AST levels among the groups II, III and IV showed that both groups III and IV which had no difference in between were significantly different in a positive way from group II (p<0.001). As to the serum ALT levels, difference between group II and group III (p<0.001) and group II and group IV (p<0.01) was found significant. No statistical difference was observed in groups I, III and IV for GSH, MDA and CAT levels of the liver. A statistical evaluation of the GSH level in group III and group IV was found to be significantly different from group II (p<0.001) without any difference between them. A similar evaluation for MDA and CAT levels among the revealed no difference between group III and group IV, however, group II showed difference with group II and group IV (p<0.05).Histological findings were in harmony with the biochemical results. We conclude that carvacrol protects the liver against defects caused by ischemia and reperfusion, and carvacrol is not hepatotoxic at the applied dosage.     

Selenium supplementation influences growth performance, antioxidant status and immune response in lambs

To investigate and compare the effect of inorganic and organic Se supplementation, 18 male lambs (24.68 ± 2.89 kg mean body weight, about 8–9 months of age) were divided into three groups of six animals in each, following randomized block design. While animals in the control group (Gr I) were fed a standard TMR containing 195 g/kg crushed maize grain, 175.5 g/kg soybean meal, 260 g/kg wheat bran, 13 g/kg mineral mixture (without Se), 6.5 g/kg common salt and 350 g/kg wheat straw, animals in Gr II and Gr III were additionally supplemented with 0.15 mg Se/kg of diet through sodium selenite (inorganic Se) and Jevsel-101 (organic Se), respectively. Experimental feeding was done for a period of 90 days. To assess the humoral immune response, all the lambs were intramuscularly inoculated with a single dose (2 mL) of Haemorrhagic septicaemia oil adjuvant vaccine on day 0; and blood samples were collected on day 0, 30, 60 and 90. Supplementation of Se had no effect on serum total cholesterol, total protein, albumin, globulin, albumin:globulin ratio, T₃, T₄, T₄:T₃ ratio; serum Ca and P levels and SGOT and SGPT activity. However, there was a significant increase in the serum Se level, RBC GSH-Px activity and humoral immune response in both the Se supplemented groups as compared to control group. Average daily gain (g) was highest (110) in Gr III, followed by Gr II (98.2) and lowest in Gr I (89.1). Thus, supplementation of organic as well as inorganic Se was found to improve the growth rate, humoral immune response and antioxidant status of the lambs; and between two sources, organic Se was more effective than inorganic Se.     

麦棉套作复合根系群体对棉株氮素吸收与分配的影响

在盆栽麦棉套作条件下,于2003～2004年设置麦棉自然根系（麦棉根系和肥水均可相互通过）、麦棉纱网隔根（肥水可相互通过,麦棉根系不能相互通过）和麦棉塑膜隔根（麦棉根系和肥水均不能相互通过）3种麦棉根系处理,运用小麦叶片15N富积标记法和15N同位素稀释法,研究麦棉复合根系群体对棉花氮素吸收与分配的影响．结果表明,在麦棉套作群体中,既存在麦棉共处期小麦对棉花根区氮素的竞争,又存在小麦根区及其所吸收氮素向棉花的转移．棉花根系吸收的15N肥料大多分配到地上部,根系分配的量较少,且麦棉自然根系处理地上部的15N标记肥料氮的吸收率（NUR）最大,纱网隔根处理次之,塑膜隔根处理最少．在麦棉共处期,麦棉自然根系处理棉花的植株从15N标记肥料中吸收的氮占其全氮的百分率（Ndff）和NUR均低于隔根处理．至棉花初花期（小麦已收获,秸秆原位埋入土壤中）,麦棉自然根系处理棉花吸收的氮素主要来源于化学肥料而非秸秆降解物．棉株不同器官所分配的15N标记肥料比例不同,棉花生殖器官中15N含量明显高于其他器官．麦棉自然根系处理棉株生物量也高于隔根处理．     

Effect of cold process monensin enriched urea molasses mineral blocks on performance of crossbred calves fed a wheat straw based diet

Twenty male crossbred calves were divided into four equal groups. Calves in groups I and II were fed wheat straw ad libitum with a concentrate mixture with or without monensin (30 mg per day per animal). Calves in groups III and IV were fed wheat straw ad libitum with 70% of the allocated concentrate mixture and had free access to urea molasses mineral block (UMMB) with or without monensin (100 ppm). Wheat straw intake was higher (P<0.05) in UMMB supplemented groups, but total dry matter (DM) and crude protein (CP) intake did not differ. ME (Mcal per day) intake was higher (P<0.05) in UMMB supplemented groups. Digestibility of DM, OM, EE, and NDF did not differ due to UMMB or monensin supplementation, although ADF digestibility was increased (P<0.01) with UMMB supplementation. Although the N balance was similar among the groups, the Ca and P balances were higher in UMMB supplemented groups. Blood glucose level was increased (P<0.05) due to monensin treatment but plasma urea N level did not differ. Average body weight gain, feed conversion efficiency, protein utilisation efficiency, and energy utilisation efficiency were higher (P>0.05) in monensin treated groups without any change in body composition. Replacing 30% of a concentrate mixture with a cold process UMMB increased the proportional contribution of wheat straw to DM intake but had no effect on animal performance. However, supplementation with monensin increased the blood glucose level, protein and energy deposition, as well as body weight gain and feed efficiency, but with no change in the wheat straw and total DM consumption.     

Plasma glucose and insulin responses in growing rats fed a total parenteral nutrition diet either intravenously or intragastrically

The effect of administering either intravenously (group I) or intragastrically (group II) a glucose-amino acid total parenteral nutrition diet over a 12-day period upon plasma glucose and insulin responses was examined in adolescent rats. Infusion of the 25% glucose - 12.2% amino acid diet at a rate of 300 kCal X kg body weight-1 X 24 h-1 supported normal weight gain over the 12-day study period in both intravenously (group I) and intragastrically (group II) alimented rats. Mean plasma glucose levels rose dramatically in both groups by the end of day 1; group I had significantly higher mean plasma insulin levels. By day 3, the group I mean plasma glucose value decreased significantly while the group II mean glucose value remained virtually unchanged. Mean plasma insulin values more than doubled in both groups with the group I level still remaining significantly above the group II level. At days 6 and 12, group I mean plasma glucose levels were significantly below group II while both groups had similar plasma insulin levels. Data from this 12-day intravenous-intragastric alimentation study reveals quite different metabolic responses compared with acute (120-180 min) studies of the enteroinsular axis.     

Methanol-fermentation protein in veal calf nutrition

In an experiment with 4 × 12 male veal calves, the influence of 0, 2.5, 5.0 and 7.5% ICI protein and sweet whey powder in a milk replacer on growth; feed efficiency; blood concentrations of urea, uric acid and allantoin; and on the iron status, colour of the meat and carcass grade of the animals was investigated. The proportion of skimmed milk powder in the milk replacer was thus reduced in protein equivalence by 5, 10 and 15% (groups II–IV).Feeding with 2.5, 5 and 7.5% ICI protein in the milk replacer gave, over the whole fattening period (60–150 kg), about the same rates of growth and feed efficiency as the exclusive use of milk protein. While the urea content in the serum was not significantly influenced by the protein sources used, the uric acid and allantoin levels of the groups given ICI protein had risen greatly at 5 weeks and at the end of fattening experiment. Despite the higher total iron supply to groups II, III and IV, the criteria indicating iron supply such as haemoglobin, haematocrit and myoglobin levels did not show any increase compared to group I. Similarly, no significant differences in meat colour and carcass grade were found among the experimental groups.For veal calves the level of ICI protein in the milk replacer can be up to 7.5% during the entire feeding period.     

Low T3 syndrome in cancer patients in relation to weight loss, intravenous hyperalimentation therapy and age

In order to investigate the relation of weight loss and intravenous hyperalimentation therapy to low T3 syndrome, serum T3, T4. rT3 and TBG were determined by radioimmunoassay in 105 cancer patients. The cancer patients were classified into 3 groups, Group I, II and III depending on the grade of weight loss, ranging up to a 5% change in weight loss from a healthy condition, from 5 to 9%, and more than 10%, respectively. Cancer patients under age 59 showed no significant difference in serum T3, T4, rT3 and TBG among these 3 groups. However serum T3 and T3/T4 in cancer patients at age 60 and over were significantly reduced in group III, compared to groups I and II. Serum rT3 values were significantly elevated in group III of elderly cancer patients. The incidence of low T3 syndrome in group III of elderly cancer patients was also significantly higher than in groups I and II. In three out of 5 cancer patients with low T3 syndrome, serum T3 values increased after the intravenous hyperalimentation therapy, whereas no significant change in serum T3 values was observed in two patients who died within one day after the final examination. It is concluded that weight loss produced different effects on peripheral conversion of T4 to T3 between cancer patients under age 59 and over age 60 and glucose plays an important role in the pathogenesis of low T3 syndrome except cases with very poor prognosis.     

The relationship between trace elements and cardiac markers in acute coronary syndromes

Previous studies have demonstrated increased serum copper and iron levels and decreased selenium and zinc levels in patients with myocardial infarction. Furthermore, the prognostic value of the levels of trace elements in myocardial infarction has been stressed. We examined serum levels of Cu, Fe, Zn and Se, as well as glutathione peroxidase (GPx), a selenoenzyme with antioxidant properties, and C-reactive protein (CRP), a marker of inflammation, in acute coronary syndromes (ACS) regarding their relationship to cardiac troponins and creatine kinase-MB mass (CK-MBm), important prognostic markers. Serum trace elements, GPx activity and CRP were determined in 70 patients with ACS who were admitted within 12 h after the onset. Differences in these parameters were evaluated in three groups of patients divided according to the levels of cardiac markers: group III consisted of patients with high increases in cTnT, cTnI and CK-MBm (> or =0.9 ng/mL, > or =1.0 ng/mL, > or =30 ng/mL, respectively), patients with milder increases in these markers were included in groups II and I consisted of patients with values just above the upper reference limits. Serum Fe levels increased significantly in group II and even more prominently in group III compared to group I (p = 0.04, 0.002, respectively). There was no significant difference between groups II and III. The increase in serum Cu was significant in group III compared to both groups II and I (p = 0.04, 0.001, respectively). There was no significant difference between groups I and II regarding Cu and Zn. The decrease in serum Se and GPx levels was significant only between groups III and I (p = 0.004 for Se and p = 0.0001 for GPx). CRP levels showed a significant increase in group III compared to groups II and I (p = 0.03 and 0.001). CRP showed a significant positive and GPx a significant negative correlation to the cardiac markers cTnT, cTnI and CK-MBm. Cu was positively correlated to all cardiac markers, while the positive correlation between Fe and cardiac markers was significant only for cTnI. Both Zn and Se were negatively correlated to cTnT, and Se was also to cTnI. In conclusion, the increase in serum levels of Cu and Fe and the decrease in serum levels of Zn and Se in patients with higher levels of troponins and CK-MBm imply that trace element levels are related to the degree of myocardial damage and thus may play a role in the pathogenesis of ischemic heart disease. The strong correlations between cardiac markers and both CRP and GPx suggest that these parameters are promising prognostic factors in acute coronary syndromes.     

麦棉套作复合根系群体对棉株氮素吸收与分配的影响

在盆栽麦棉套作条件下,于2003～2004年设置麦棉自然根系(麦棉根系和肥水均可相互通过)、麦棉纱网隔根(肥水可相互通过,麦棉根系不能相互通过)和麦棉塑膜隔根(麦棉根系和肥水均不能相互通过)3种麦棉根系处理,运用小麦叶片¹⁵N富积标记法和¹⁵N同位素稀释法,研究麦棉复合根系群体对棉花氮素吸收与分配的影响.结果表明,在麦棉套作群体中,既存在麦棉共处期小麦对棉花根区氮素的竞争,又存在小麦根区及其所吸收氮素向棉花的转移.棉花根系吸收的¹⁵N肥料大多分配到地上部,根系分配的量较少,且麦棉自然根系处理地上部的¹⁵N标记肥料氮的吸收率(NUR)最大,纱网隔根处理次之,塑膜隔根处理最少.在麦棉共处期,麦棉自然根系处理棉花的植株从¹⁵N标记肥料中吸收的氮占其全氮的百分率(Ndff)和NUR均低于隔根处理.至棉花初花期(小麦已收获,秸秆原位埋入土壤中),麦棉自然根系处理棉花吸收的氮素主要来源于化学肥料而非秸秆降解物.棉株不同器官所分配的¹⁵N标记肥料比例不同,棉花生殖器官中¹⁵N含量明显高于其他器官.麦棉自然根系处理棉株生物量也高于隔根处理.     

Effect of zinc supplementation from different sources on growth, nutrient digestibility, blood metabolic profile, and immune response of male guinea pigs

Forty weaned male guinea pigs of 208.20±6.62 g mean body weight were divided into 4 groups of 10 animals in a randomized block design. All of the guinea pigs were fed a basal diet [25% ground maize hay, 30% ground maize grain, 22% ground chickpea (Cicer arietinum L.), 9.5% deoiled rice bran, 6% soybean meal, 6% fish meal, 1.45% mineral supplement (without Zn) and 0.05% ascorbic acid] and available green fodder. Group I served as the control (no Zn supplementation), whereas 20 ppm Zn was added in the diet in groups II, III, and IV either as zinc sulfate (ZnSO₄), zinc amino acid complex (ZAAC), and ZnSO₄ ⁺ ZAAC in equal parts, respectively. Experimental feeding lasted for 70 d, including a 3-d digestibility trial. Blood was collected through cardiac puncture from four animals in each group at d 0 and subsequently at the end of experimental feeding. After 40 d of experimental feeding, four animals from each group were injected with 0.4 mL of Brucella abortus cotton strain-19 vaccine to assess the humoral immune response of the animals. After 10 wk of study, four animals from each group were sacrificed to study the concentration of Zn, Cu, Co, Fe, and Mn in the liver, pancreas and spleen. Results revealed no significant difference in the feed intake, body weight gain, and digestibility of the nutrients, except for crude protein (CP) digestibility, which was significantly (p<0.05) lower in group IV. Although concentrations of serum glucose, Ca, and P and the albumin:globulin (A:G) ratio were similar in the different groups, the total protein, albumin, and serum alkaline phosphatase activity were higher in all of the Zn-supplemented groups on d 70. The serum Zn levels at the end of experimental feeding were significantly higher in groups II and III, whereas serum Mn levels were found to be significantly (p<0.05) higher in groups III and IV. The organ weights (as percentage of body weights) did not show any differences among the treatment groups. Although the Mn concentration was significantly (p<0.05) higher in the pancreas, the Cu concentration was significantly (p<0.05) reduced in the spleen in all of the Zn-supplemented groups. The humoral immune response (antibody titer values) on d 14 of vaccination was significantly (p<0.05) higher in all of the Zn-supplemented groups. It was concluded that the 20-ppm level of Zn in the diet might be adequate for growth and nutrient utilization in guinea pigs, but supplementation of 20-ppm zinc significantly improved the immune response and impact was more prominent with the ZAAC (organic source) compared to ZnSO₄ (inorganic source).     

Effect of administration of anaerobic fungi isolated from cattle and wild blue bull (Boselaphus tragocamelus) on growth rate and fibre utilization in buffalo calves

Fifteen Murrah buffalo calves (age about 10 months, 163-176 kg BW) were divided into three groups. Group I (Control) was fed a complete feed mixture consisted of 50% wheat straw and 50% concentrate mixture (contained per kg: maize 330 g, groundnut cake 210 g, mustard cake 120 g, wheat bran 200 g, de-oiled rice bran 110 g, mineral mixture 20 g and common salt 10 g) along with 2 kg green oats per animal and day to meet the vitamin A requirements. Calves of Groups II and III were fed with the Control diet supplemented with Orpinomyces sp. C-14 and Piromyces sp. WNG-12 cultures, respectively. The digestibility of DM was significantly highest with Piromyces sp. WNG-12 in Group III (62.2%) followed by Orpinomyces sp. C-14 in Group II (60.3%), and Control (53.5%). A similar pattern of increase in digestibility of crude protein and cell-wall contents was observed in treatment groups. The digestible energy in terms of percent total digestible nutrients was also significantly enhanced in Groups II (56.6%) and III (59.9%) when compared to Control (49.2%). The rumen fermentation parameters such as pH and NH3-N were found to be lower, whereas total nitrogen, tricarboxylic acid precipitable-, nitrogen, total volatile fatty acids and zoospore counts per millilitre of rumen liquor were significantly higher in fungal administered groups. After administration of fungal cultures, improvements of animal growth rate (i.e. body weight gain) and feed efficiency were also observed.     

Effect of Organic Selenium Supplementation on Growth, Se Uptake, and Nutrient Utilization in Guinea Pigs

Forty weaned male guinea pigs (Cavia porcellus) of 152.6?±?7.96 g mean body weight were divided into four equal groups and fed a common basal diet comprised of 25% ground cowpea (Vigna unguiculata) hay, 30% ground maize (Zea mays) grain, 22% ground gram (Cicer arietinum) grain, 9.5% deoiled rice (Oryza sativa) bran, 6% soybean (Glycine max) meal, 6% fish meal, 1.5% mineral mixture (without Se), and ascorbic acid at 200 mg/kg to meet their nutrient requirements along with 0, 0.1, 0.2, and 0.3 ppm of organic selenium (Se) in groups I, II, III, and IV, respectively. Experimental feeding lasted for a period of 10 weeks, during which, daily feed intake and weekly body weights were recorded. Intake and digestibility of dry matter, organic matter, ether extract, crude fiber, and nitrogen-free extract as well as uptake of calcium and phosphorus were similar (P?>?0.05) among the four groups. Feed:gain ratio was also similar (P?>?0.05) in the four groups. However, digestibility of crude protein was significantly (P?<?0.001) higher in group II supplemented with 0.1 ppm organic Se as compared to other three group. Intake and absorption of Se was significantly (P?<?0.001) higher in all the Se supplemented groups as compared to control group. Average daily gain (ADG) was significantly (P?<?0.05) higher in group II (3.16 g/day) and III (3.38 g/day) as compared to group I (2.88 g/day). However, ADG in group IV (supplemented 0.3 ppm organic Se) was significantly (P?<?0.05) lower (2.83 g/day) than group II and III, but comparable (P?>?0.05) to group I. Findings of the present experiment suggests that Se requirements of guinea pigs are ≥0.2 ppm, as supplementation of 0.1 ppm organic Se in the diet (having 0.1 ppm Se) not only enhanced their growth rate but also improved the protein utilization.     

稳定性氮肥配合秸秆还田对水稻产量及N2O和CH4排放的影响

以中国科学院辽宁沈阳农田生态系统国家野外科学观测研究站连续两年的试验平台为依托,以潮棕壤为供试土壤,开展了稳定性氮肥配合秸秆还田对水稻产量及N₂O和CH₄排放的影响研究,设置对照(CK)、尿素(U)、尿素+脲酶抑制剂+硝化抑制剂(U+I)、秸秆还田(S)、秸秆还田+尿素(S+U)、秸秆还田+尿素+脲酶抑制剂+硝化抑制剂(S+U+I)6个处理.结果表明: 与CK相比,尿素显著提高了水稻产量、N₂O和CH₄累积排放及全球增温潜势.硝化抑制剂和脲酶抑制剂与尿素配施可显著减缓N₂O的累积排放.秸秆还田显著增加了N₂O和CH₄累积排放、全球增温潜势和温室气体排放强度.S+U+I处理水稻产量最高,但温室气体排放强度也显著高于其他处理;U+I处理产量略低于S+U+I,但温室气体排放强度最小.秸秆单独还田处理作物产量与对照相比无显著差异.在东北潮棕壤发育的水田中,S+U+I和U+I是相对较优的施肥模式.     

稳定性氮肥配合秸秆还田对水稻产量及N2O和CH4排放的影响

以中国科学院辽宁沈阳农田生态系统国家野外科学观测研究站连续两年的试验平台为依托,以潮棕壤为供试土壤,开展了稳定性氮肥配合秸秆还田对水稻产量及N₂O和CH₄排放的影响研究,设置对照(CK)、尿素(U)、尿素+脲酶抑制剂+硝化抑制剂(U+I)、秸秆还田(S)、秸秆还田+尿素(S+U)、秸秆还田+尿素+脲酶抑制剂+硝化抑制剂(S+U+I)6个处理.结果表明: 与CK相比,尿素显著提高了水稻产量、N₂O和CH₄累积排放及全球增温潜势.硝化抑制剂和脲酶抑制剂与尿素配施可显著减缓N₂O的累积排放.秸秆还田显著增加了N₂O和CH₄累积排放、全球增温潜势和温室气体排放强度.S+U+I处理水稻产量最高,但温室气体排放强度也显著高于其他处理;U+I处理产量略低于S+U+I,但温室气体排放强度最小.秸秆单独还田处理作物产量与对照相比无显著差异.在东北潮棕壤发育的水田中,S+U+I和U+I是相对较优的施肥模式.     

Natural and endotoxin-induced atresia of preantral and early antral follicles is characterized by DNA internucleosomal cleavage

Preantral follicles (PAF) and early antral follicles (EAF) were isolated from bovine ovaries and classified under a stereomicroscope as atretic or healthy. The atretic follicles were all considered as group I (in vivo atresia), whereas healthy follicles were assigned to five groups (group II, in vivo normal control; group III, in vitro normal control; group IV, in vitro induced atresia; groups V and VI, Lipopolysaccharide (LPS)-induced atresia in vitro). Group I and II follicles were immediately snap-frozen (−70°C) until DNA extraction, whereas group III–VI follicles were incubated (39°C, 5% CO₂, 95% air) for periods up to 72 hr under various conditions. Group III follicles were maintained in complete medium (M199, bovine calf serum, sodium pyruvate, epidermal growth factor, insulin, transferrin, sodium selenite, penicillin, streptomycin, and amphotericin), whereas group IV follicles were incubated in the same medium, but without serum. Group V and VI follicles were maintained in complete medium, but in the presence of LPS (10 or 50 μ/ml, respectively). Results showed that follicles incubated in the absence of serum and those exposed to both doses of LPS became atretic. DNA isolated from all atretic follicles showed fragmentation typical of that described for apoptosis; this was also confirmed by in situ DNA labeling and histology. Atretic follicles did not produce estradiol (P < 0.001), but progesterone values increased with follicle size (P < 0.001) and time of incubation (P < 0.001). We concluded that in the absence of serum or in the presence of LPS, follicles undergo atresia via apoptosis. © 1996 Wiley-Liss, Inc.